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1.
Anim. Reprod. (Online) ; 19(1): e253226, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1461553

Resumo

This study aimed to evaluate the effect of synchronization with prostaglandin F2α in Baixadeiro mares during the rainy and dry seasons. Fourteen mares were synchronized by administering two doses of 1 mL prostaglandin PGF 2α and monitored by rectal palpation and ultrasound for the assessment of follicular development and uterine echotexture. Of this total, nine mares allowed the collection of blood, in which the blood was collected by venipuncture of the jugular vein to determine progesterone (P4) by ELISA. Mares showed no differences (P > 0.05) in weight, body score condition (BSC), tone, uterine edema, frequency of ovulation, synchronization interval, estrus, and the total number of follicles between periods. However, there was a difference in large increased follicle diameter (P < 0.05) during the dry season. The average concentrations of P4 in mares differed (P < 0.05) between the pre- and post-ovulatory phases for both seasons and after ovulation, with higher concentrations in the rainy season. Furthermore, statistical differences in daily light (P < 0.05) were observed between the dry and rainy periods. Thus, we conclude that mares from the genetic grouping Baixadeiro showed no reproductive seasonality, though there was a difference in luminosity between the rainy and dry seasons. The treatment with two doses of PGF 2α was effective in synchronizing the mares, promoting the return of estrus in the dry and rainy periods. The mares remaining cyclically active throughout the year provided there were appropriate forage availability and quality levels to allow for normal values of body weight and condition.


Assuntos
Feminino , Animais , Cavalos/fisiologia , Folículo Ovariano , Prostaglandinas , Sincronização do Estro
2.
Anim. Reprod. (Online) ; 19(1): e20200050, 2022. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1360102

Resumo

Abstract This study aimed to evaluate the effect of synchronization with prostaglandin F2α in Baixadeiro mares during the rainy and dry seasons. Fourteen mares were synchronized by administering two doses of 1 mL prostaglandin PGF 2α and monitored by rectal palpation and ultrasound for the assessment of follicular development and uterine echotexture. Of this total, nine mares allowed the collection of blood, in which the blood was collected by venipuncture of the jugular vein to determine progesterone (P4) by ELISA. Mares showed no differences (P > 0.05) in weight, body score condition (BSC), tone, uterine edema, frequency of ovulation, synchronization interval, estrus, and the total number of follicles between periods. However, there was a difference in large increased follicle diameter (P < 0.05) during the dry season. The average concentrations of P4 in mares differed (P < 0.05) between the pre- and post-ovulatory phases for both seasons and after ovulation, with higher concentrations in the rainy season. Furthermore, statistical differences in daily light (P < 0.05) were observed between the dry and rainy periods. Thus, we conclude that mares from the genetic grouping Baixadeiro showed no reproductive seasonality, though there was a difference in luminosity between the rainy and dry seasons. The treatment with two doses of PGF 2α was effective in synchronizing the mares, promoting the return of estrus in the dry and rainy periods. The mares remaining cyclically active throughout the year provided there were appropriate forage availability and quality levels to allow for normal values of body weight and condition.

3.
Anim. Reprod. ; 19(1): e253226, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-765783

Resumo

This study aimed to evaluate the effect of synchronization with prostaglandin F2α in Baixadeiro mares during the rainy and dry seasons. Fourteen mares were synchronized by administering two doses of 1 mL prostaglandin PGF 2α and monitored by rectal palpation and ultrasound for the assessment of follicular development and uterine echotexture. Of this total, nine mares allowed the collection of blood, in which the blood was collected by venipuncture of the jugular vein to determine progesterone (P4) by ELISA. Mares showed no differences (P > 0.05) in weight, body score condition (BSC), tone, uterine edema, frequency of ovulation, synchronization interval, estrus, and the total number of follicles between periods. However, there was a difference in large increased follicle diameter (P < 0.05) during the dry season. The average concentrations of P4 in mares differed (P < 0.05) between the pre- and post-ovulatory phases for both seasons and after ovulation, with higher concentrations in the rainy season. Furthermore, statistical differences in daily light (P < 0.05) were observed between the dry and rainy periods. Thus, we conclude that mares from the genetic grouping Baixadeiro showed no reproductive seasonality, though there was a difference in luminosity between the rainy and dry seasons. The treatment with two doses of PGF 2α was effective in synchronizing the mares, promoting the return of estrus in the dry and rainy periods. The mares remaining cyclically active throughout the year provided there were appropriate forage availability and quality levels to allow for normal values of body weight and condition.(AU)


Assuntos
Animais , Feminino , Cavalos/fisiologia , Folículo Ovariano , Sincronização do Estro , Prostaglandinas
4.
Semina ciênc. agrar ; 41(1): 181-190, Jan.-Feb. 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1501726

Resumo

The objective of this study was to evaluate the morphology, morphometry, and membrane integrity of epididymal spermatozoa of spotted pacas using spermatic cells collected from the epididymal tails of five animals. The flotation method using the ACP-123® and Botusemen Special® extenders was performed, and samples were stained in Diff-Quick and eosin-nigrosine. Descriptive statistics of data were obtained and Students t-test was performed. The morphology of 200 Diff-Quick-stained spermatozoa showed that they had an oval head with three vesicles in the acrosomal region, a midpiece, an elongated tail; moreover, 27% of the spermatozoa exhibited cellular defects. The morphometry of 100 sperm cells (analyzed with an optical microscope and the EZ Leica LAS software for Windows) presented the following measurements (mean ± SD): total length 43.87 ± 4.91 μm, head 7.54 ± 0.82 μm, midpiece 5.35 ± 0.83 μm, tail 30.72 ± 2.55 μm, and head width 5.30 ± 0.68 μm. Of the 2,000 cells stained with eosin-nigrosine for membrane integrity evaluation, 83.8% diluted in ACP-123® and 72.9% diluted in Botusemen® had intact membranes. The results of this study suggest that epididymal spermatozoa of pacas can be used in assisted reproduction programs; moreover, our study adds knowledge to the reproductive biology of wild animals, and encourages further research on the role of the three acrosomal vesicles present in this species.


Com o objetivo de avaliar a morfologia, a morfometria e a integridade de membrana dos espermatozoides epididimários de paca, células espermáticas oriundas da cauda do epidídimo foram obtidas de cinco animais pelo método de flutuação, utilizando os diluidores ACP-123 ® e Botusemen Special®, coradas em Panótico rápido e Eosina-Nigrosina. Os dados foram analisados por estatística descritiva e teste t de Student. A morfologia de 200 espermatozoides corados em Panótico rápido evidenciou que os mesmos possuíam: cabeça ovalada com três vesículas na região acrossomal, peça intermediária, cauda alongada, sendo os defeitos celulares de 27%. A morfometria de 100 células espermáticas (efetuada com microscópio óptico e softwares EZ Leica LAS de aquisição de imagens para sistemas operacionais Windows) apresentou as seguintes medidas (média ± d.p): comprimento total 43,87 ± 4,91 µm, cabeça 7,54 ± 0,82 µm, peça intermediária 5,35 ± 0,83 µm, cauda 30,72 ± 2,55 µm e largura da cabeça 5,30 ± 0,68 µm. Das 2.000 células coradas em Eosina-Nigrosina para avaliação da integridade da membrana, 83,8 % das diluídas em ACP 123 ® e 72,9 % das diluídas em Botusemen® estavam com as membranas intactas. Os resultados sugerem que espermatozoides epididimários de pacas podem ser utilizados em técnicas de reprodução assistida, agregam conhecimentos a esta área e suscitam novos estudos sobre o papel das três vesículas acrossomais características nesta espécie.


Assuntos
Cuniculidae , Epididimo , Espermatozoides/fisiologia , Membranas/fisiologia , Sêmen/fisiologia
5.
Semina Ci. agr. ; 41(1): 181-190, Jan.-Feb. 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-746201

Resumo

The objective of this study was to evaluate the morphology, morphometry, and membrane integrity of epididymal spermatozoa of spotted pacas using spermatic cells collected from the epididymal tails of five animals. The flotation method using the ACP-123® and Botusemen Special® extenders was performed, and samples were stained in Diff-Quick and eosin-nigrosine. Descriptive statistics of data were obtained and Students t-test was performed. The morphology of 200 Diff-Quick-stained spermatozoa showed that they had an oval head with three vesicles in the acrosomal region, a midpiece, an elongated tail; moreover, 27% of the spermatozoa exhibited cellular defects. The morphometry of 100 sperm cells (analyzed with an optical microscope and the EZ Leica LAS software for Windows) presented the following measurements (mean ± SD): total length 43.87 ± 4.91 μm, head 7.54 ± 0.82 μm, midpiece 5.35 ± 0.83 μm, tail 30.72 ± 2.55 μm, and head width 5.30 ± 0.68 μm. Of the 2,000 cells stained with eosin-nigrosine for membrane integrity evaluation, 83.8% diluted in ACP-123® and 72.9% diluted in Botusemen® had intact membranes. The results of this study suggest that epididymal spermatozoa of pacas can be used in assisted reproduction programs; moreover, our study adds knowledge to the reproductive biology of wild animals, and encourages further research on the role of the three acrosomal vesicles present in this species.(AU)


Com o objetivo de avaliar a morfologia, a morfometria e a integridade de membrana dos espermatozoides epididimários de paca, células espermáticas oriundas da cauda do epidídimo foram obtidas de cinco animais pelo método de flutuação, utilizando os diluidores ACP-123 ® e Botusemen Special®, coradas em Panótico rápido e Eosina-Nigrosina. Os dados foram analisados por estatística descritiva e teste t de Student. A morfologia de 200 espermatozoides corados em Panótico rápido evidenciou que os mesmos possuíam: cabeça ovalada com três vesículas na região acrossomal, peça intermediária, cauda alongada, sendo os defeitos celulares de 27%. A morfometria de 100 células espermáticas (efetuada com microscópio óptico e softwares EZ Leica LAS de aquisição de imagens para sistemas operacionais Windows) apresentou as seguintes medidas (média ± d.p): comprimento total 43,87 ± 4,91 µm, cabeça 7,54 ± 0,82 µm, peça intermediária 5,35 ± 0,83 µm, cauda 30,72 ± 2,55 µm e largura da cabeça 5,30 ± 0,68 µm. Das 2.000 células coradas em Eosina-Nigrosina para avaliação da integridade da membrana, 83,8 % das diluídas em ACP 123 ® e 72,9 % das diluídas em Botusemen® estavam com as membranas intactas. Os resultados sugerem que espermatozoides epididimários de pacas podem ser utilizados em técnicas de reprodução assistida, agregam conhecimentos a esta área e suscitam novos estudos sobre o papel das três vesículas acrossomais características nesta espécie.(AU)


Assuntos
Espermatozoides/fisiologia , Membranas/fisiologia , Cuniculidae , Epididimo , Sêmen/fisiologia
6.
R. bras. Reprod. Anim. ; 40(4): 380-381, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: vti-24151

Resumo

The objective of this study was to evaluate the effect of n-type insulin on sheep semen on the time andtemperature motility after 60 minutes of incubation at 45ºC. To therefore 7 sheep were used, the collects weremade with the aid of the Electro ejaculator. The citrate-yolk diluent was used to dilute the ejaculates (25x106sptz/ ml) using quail egg yolk. Each ejaculate was divided into four equal fractions, corresponding to thetreatments: control group (Gcont), using only tris-gem; Group 50 (G500) Diluent plus 50 IU / ml N-type Insulin;Group 100 (G100) diluent plus 100 IU / ml Insulin type N; Group 200 (G200) diluent plus 200 UI / ml N-typeInsulin. After dilution, the semen remained in a water bath at 45°C for the fast thermoresistance test on the timeevaluation (0, 20, 40, 60 Minutes), for sperm motility and vigor. The data, were submitted to the t test, and thosethat did not present parameters with normal distribution were compared by the Friedman test. According to theobtained data, the insulin in the concentrations used experimentally, it was not possible to verify positive effectof the supplementation of the same, and high concentrations decrease the sperm viability.(AU)


Assuntos
Animais , Masculino , Ovinos/embriologia , Motilidade dos Espermatozoides/fisiologia , Insulina
7.
Rev. bras. reprod. anim ; 40(4): 380-381, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: biblio-1492308

Resumo

The objective of this study was to evaluate the effect of n-type insulin on sheep semen on the time andtemperature motility after 60 minutes of incubation at 45ºC. To therefore 7 sheep were used, the collects weremade with the aid of the Electro ejaculator. The citrate-yolk diluent was used to dilute the ejaculates (25x106sptz/ ml) using quail egg yolk. Each ejaculate was divided into four equal fractions, corresponding to thetreatments: control group (Gcont), using only tris-gem; Group 50 (G500) Diluent plus 50 IU / ml N-type Insulin;Group 100 (G100) diluent plus 100 IU / ml Insulin type N; Group 200 (G200) diluent plus 200 UI / ml N-typeInsulin. After dilution, the semen remained in a water bath at 45°C for the fast thermoresistance test on the timeevaluation (0, 20, 40, 60 Minutes), for sperm motility and vigor. The data, were submitted to the t test, and thosethat did not present parameters with normal distribution were compared by the Friedman test. According to theobtained data, the insulin in the concentrations used experimentally, it was not possible to verify positive effectof the supplementation of the same, and high concentrations decrease the sperm viability.


Assuntos
Masculino , Animais , Motilidade dos Espermatozoides/fisiologia , Ovinos/embriologia , Insulina
8.
R. bras. Reprod. Anim. ; 40(4): 378-379, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: vti-24150

Resumo

This study aimed to evaluate the effect of insulin on the membrane integrity evaluated by the eosin testand nigrosine in ovine semen. Seven sheep were used, harvest were made with the aid of eletroejaculator. Theyolk-citrate extender was used for dilution of the ejaculate (25x106 sperm / mL) using quail's egg yolk. Eachejaculate was divided into four equal fractions, corresponding to treatments: control group (Gcont) using onlydilutive citrat gem; Group 50 (G50) plus dilutive 50UI/ml insulin type N; Group 100 (G100) plus dilutive 100IU/Ml Insulin type N; Group 200 (G200) plus dilutive 200 IU/Ml Insulin type N. After dilution, the semenremained in water - bath at 45°C to perform the eosin test and nigrosine for evaluation by time (0, 20, 40 and 60minutes) for membrane integrity. Thus, the use of insulin does not preserve the integrity of the membranesduring the incubation period of 45C, with a gradual decrease due to stress caused by time and temperature atwhich the semen was subjected.(AU)


Assuntos
Animais , Ovinos/embriologia , Ovinos/fisiologia , Membrana Celular/classificação , Membrana Celular/metabolismo , Espermatozoides/citologia , Espermatozoides/enzimologia , Insulina
9.
Rev. bras. reprod. anim ; 40(4): 378-379, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: biblio-1492307

Resumo

This study aimed to evaluate the effect of insulin on the membrane integrity evaluated by the eosin testand nigrosine in ovine semen. Seven sheep were used, harvest were made with the aid of eletroejaculator. Theyolk-citrate extender was used for dilution of the ejaculate (25x106 sperm / mL) using quail's egg yolk. Eachejaculate was divided into four equal fractions, corresponding to treatments: control group (Gcont) using onlydilutive citrat gem; Group 50 (G50) plus dilutive 50UI/ml insulin type N; Group 100 (G100) plus dilutive 100IU/Ml Insulin type N; Group 200 (G200) plus dilutive 200 IU/Ml Insulin type N. After dilution, the semenremained in water - bath at 45°C to perform the eosin test and nigrosine for evaluation by time (0, 20, 40 and 60minutes) for membrane integrity. Thus, the use of insulin does not preserve the integrity of the membranesduring the incubation period of 45C, with a gradual decrease due to stress caused by time and temperature atwhich the semen was subjected.


Assuntos
Animais , Espermatozoides/citologia , Espermatozoides/enzimologia , Membrana Celular/classificação , Membrana Celular/metabolismo , Ovinos/embriologia , Ovinos/fisiologia , Insulina
10.
R. bras. Reprod. Anim. ; 40(4): 238-240, Out-Dez. 2016. tab, graf
Artigo em Português | VETINDEX | ID: vti-24030

Resumo

Seminal plasma is a fluid with essential role in sperm functions in vivo, from ejaculation to fertilization.Among the hormones present in this medium, insulin stands out, due to its key role in the structure and motility,favoring fertilization. Insulin acts as preservation factor not able sperm and may be the crux of spermpreservation when using cryogenic processes. This study aimed to evaluate the metabolic and structuralcondition of bovine sperm cells after freezing using extenders plus different types of insulin and different types ofegg yolk. Our results showed that sperm motility was not affected by treatments used (insulin and yolk). Inconclusion, the type of egg yolk, the paw (Anas platyrhynchos), increased the viability of cryopreserved spermcells, regardless of the type of insulin used.(AU)


Assuntos
Animais , Bovinos , Células-Tronco Germinativas Adultas/classificação , Células-Tronco Germinativas Adultas/metabolismo , Células-Tronco Germinativas Adultas/fisiologia , Criopreservação , Insulina , Motilidade dos Espermatozoides
11.
R. bras. Reprod. Anim. ; 40(4): 202-204, Out-Dez. 2016. tab, graf
Artigo em Português | VETINDEX | ID: vti-24013

Resumo

The objective was to monitor ovarian follicular development cows Gir, submitted to superovulationprotocol. Using 10 heifers, subject to three exam sessions gynecologic these being on day 0, day 4 and day 7,where on day 0 performed before beginning the superovulation protocol in order to select those that showed nochange in the reproductive tract and had corpus luteum active, while on day 4 and day 7 held in the days ofsuperstimulatory protocol, in order to quantify the follicles and evaluate follicular growth each female. With themeasurement of the follicles, it resulted three-averages 7,6 mm; 7,7mm and 10,0mm for the respective day, day0, day 4 and day 7. It was concluded that cows submitted to superovulation protocol presented ovarian folliclegrowth over the days evaluated by ultrasound and significant number of corpora lutea at the moment of embryocollection.(AU)


Assuntos
Animais , Feminino , Bovinos/anatomia & histologia , Bovinos/fisiologia , Superovulação/fisiologia , Biotecnologia
12.
Rev. bras. reprod. anim ; 40(4): 202-204, Out-Dez. 2016. tab, graf
Artigo em Português | VETINDEX | ID: biblio-1492234

Resumo

The objective was to monitor ovarian follicular development cows Gir, submitted to superovulationprotocol. Using 10 heifers, subject to three exam sessions gynecologic these being on day 0, day 4 and day 7,where on day 0 performed before beginning the superovulation protocol in order to select those that showed nochange in the reproductive tract and had corpus luteum active, while on day 4 and day 7 held in the days ofsuperstimulatory protocol, in order to quantify the follicles and evaluate follicular growth each female. With themeasurement of the follicles, it resulted three-averages 7,6 mm; 7,7mm and 10,0mm for the respective day, day0, day 4 and day 7. It was concluded that cows submitted to superovulation protocol presented ovarian folliclegrowth over the days evaluated by ultrasound and significant number of corpora lutea at the moment of embryocollection.


Assuntos
Feminino , Animais , Biotecnologia , Bovinos/anatomia & histologia , Bovinos/fisiologia , Superovulação/fisiologia
13.
Rev. bras. reprod. anim ; 40(4): 238-240, Out-Dez. 2016. tab, graf
Artigo em Português | VETINDEX | ID: biblio-1492249

Resumo

Seminal plasma is a fluid with essential role in sperm functions in vivo, from ejaculation to fertilization.Among the hormones present in this medium, insulin stands out, due to its key role in the structure and motility,favoring fertilization. Insulin acts as preservation factor not able sperm and may be the crux of spermpreservation when using cryogenic processes. This study aimed to evaluate the metabolic and structuralcondition of bovine sperm cells after freezing using extenders plus different types of insulin and different types ofegg yolk. Our results showed that sperm motility was not affected by treatments used (insulin and yolk). Inconclusion, the type of egg yolk, the paw (Anas platyrhynchos), increased the viability of cryopreserved spermcells, regardless of the type of insulin used.


Assuntos
Animais , Bovinos , Criopreservação , Células-Tronco Germinativas Adultas/classificação , Células-Tronco Germinativas Adultas/fisiologia , Células-Tronco Germinativas Adultas/metabolismo , Insulina , Motilidade dos Espermatozoides
14.
R. bras. Reprod. Anim. ; 40(4): 503-504, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: vti-24232

Resumo

Embryo transfer in mares is a very important biotechnology to improve genetic material. The aim of thepresent study was to evaluate the best day for embryo transfer, according to the synchronization between thedonor and the recipient mare, evaluating quality and stage of the collected embryo. It was obtained an embryorecovery rate of 56.06% of the embryo flushes, a rate that was similar for D7, D8 and D9. There was nostatistical difference relating to embryo stage and quality and collection day, and neither to the pregnancy rateafter the transfer, according to the embryo age.(AU)


Assuntos
Animais , Feminino , Prenhez , Transferência Embrionária/efeitos adversos , Transferência Embrionária/veterinária , Cavalos/embriologia , Biotecnologia/estatística & dados numéricos
15.
Rev. bras. reprod. anim ; 40(4): 503-504, Out-Dez. 2016. tab
Artigo em Português | VETINDEX | ID: biblio-1492361

Resumo

Embryo transfer in mares is a very important biotechnology to improve genetic material. The aim of thepresent study was to evaluate the best day for embryo transfer, according to the synchronization between thedonor and the recipient mare, evaluating quality and stage of the collected embryo. It was obtained an embryorecovery rate of 56.06% of the embryo flushes, a rate that was similar for D7, D8 and D9. There was nostatistical difference relating to embryo stage and quality and collection day, and neither to the pregnancy rateafter the transfer, according to the embryo age.


Assuntos
Feminino , Animais , Cavalos/embriologia , Prenhez , Transferência Embrionária/efeitos adversos , Transferência Embrionária/veterinária , Biotecnologia/estatística & dados numéricos
16.
Ciênc. vet. tróp ; 14(1/2/3): 29-33, jan.-dez. 2011.
Artigo em Português | VETINDEX | ID: biblio-1366843

Resumo

A maturação oocitária é um ponto determinante para a aquisição da capacidade do oócito em ser fecundado, sendo regulada pela combinação de modificações nas células do estroma ovariano, pela influência de hormônios esteroides, de gonado- tropinas hipofisárias, dos fatores de crescimento e de certas proteínas, como por exemplo, a proteína quinase ativada por mitógeno e o fator promotor de maturação, que possibilitam o desenvolvimento embrionário, mas que requerem interações altamente dinâmicas no compartimento folicular para que se possa determinar o ponto de parada e reinício da maturação, para, então, sofrer a ovulação.(AU)


Oocyte maturation is defined by the acquisition of full capability by the female gamete to be fertilized. It is regulated by a combination of several factors including: modifications of the follicular cells, steroids, gonadotropins, growth factors, and certain proteins (e.g. mitogen activated protein kinase and maturation promoting factor). Mitogen activated protein kinase and maturation promoting factors have deminstrated to assist the embryonary development of the oocyte. This is a highly dynamic and finely regulated path in the follicle. These path will determine the stop ping and restarting points of the oocyte maturation, in order to later allow ovulation. Therefore, the aim of this publication is to describe fundamental physiological means of the oocyte maturation in mammals.(AU)


Assuntos
Animais , Feminino , Oócitos , Fator Promotor de Maturação , Células Estromais , Proteínas Quinases Ativadas por Mitógeno , Desenvolvimento Embrionário , Gonadotropinas
17.
Ciênc. vet. tróp ; 14(1/2/3): 10-19, jan.-dez. 2011.
Artigo em Português | VETINDEX | ID: biblio-1366828

Resumo

A eficiência reprodutiva obtida no rebanho é dependente da fertilidade de ambos os progenitores. Entretanto, tende-se a atribuir maior responsabilidade pelos baixos índices de fertilidade ao final da estação de monta à fêmea, negligenciando-se a avaliação do reprodutor frente a estes resultados. Contudo, deve-se conferir maior importância às variáveis relacionadas ao macho, as quais podem contribuir diretamente para a determinação de menores taxas de fertilidade. Dentre essas variáveis destaca-se a qualidade seminal, sendo primariamente avaliada pela motilidade e morfologia espermática. No entanto, atualmente empregam-se exa- mes mais minuciosos, como: identificação de fatores de crescimento no plasma seminal, razão colesterol/fosfolipídios na membrana espermática, integridade das membranas acrossomal, mitocondrial e espermática exigindo, desta maneira, um conhecimento mais abrangente, por parte do examinador, para que se possa ter um maior poder diagnóstico e preditivo da fertilidade do reprodutor a ser utilizado.(AU)


Reproductive efficiency in the herd depends on the fertility of both mates. However, we tend to blame low fertility at the end of the breeding season to the female, ne- glecting to assess the male facing these results. However, more emphasis should be given on variables related to the male which can contribute directly to the de- termination of lower fertility rate. Among these variables, sperm quality is pointed out, which is primarily evaluated by motility and morphology. However, nowadays more detailed examinations are employed, such as identification of growth factors in seminal plasma, cholesterol/phospholipids ratio in the sperm membrane, acroso- me, mitochondrial and sperm membrane integrity, requiring a more comprehensive knowledge on the part of the examiner, who may have a greater diagnostic and predictive power of the fertility of the breeder to be used.(AU)


Assuntos
Animais , Masculino , Fosfolipídeos , Fator de Crescimento Insulin-Like I , Análise do Sêmen , Fertilidade , Cavalos
18.
Ciênc. vet. tróp ; 13(1/2/3): 17-23, jan.-dez. 2010.
Artigo em Português | VETINDEX | ID: biblio-1480449

Resumo

O hipotálamo, considerado ponto chave do comando reprodutivo, produz um hormônio decapeptídeo, o GnRH, que é liberado no sistema porta hipotalamico-hipofisário para estimular a sintese e a liberação de gonadotropinas, responsáveis pela dinamica folicular ovariana, produção de estrógeno, ovulação e luteinização do corpo lúteo, conjuntamente a outros hormônios, como por exemplo, o fator de crescimento semelhante à insulina (IGF) e a proteina plasmática associada à prenhez (PAPP-A) que comandam os principais sinais comportamentais de exteriorização do estro e os eventos que determinam a ovulação. Dentro desse contexto, destaca-se a liberação de prostaglandina folicular, que inicia a lise da parede do folículo, a qual está associada com o aumento da enzima óxido nítrico sintase endotelial (NOS), que aumenta o fluxo sanguíneo ovariano e, consequentemente, ativa os peptídeos vasoativos: angiotensina II (Ang II), endotelina-1 (ET-1) e o peptideo natriurético atrial (ANP), representando parte da grande rede integrada de hormônios e metabólitos envolvidos no crescimento, desenvolvimento e ovulação folicular. Dessa forma, faz-se necessário amplo conhecimento dos acontecimentos que cercam a formação e a ovulação do oócito na égua, para que se possa imprimir adequado manejo reprodutivo às fêmeas.


Considered as a key point in the reproduction command, the hypothalamus produces a decapeptide hormone, GnRH, which is released in the hypothalamic-pituitary system to stimulate the synthesis and secretion of gonadotropins, responsible for the ovarian follicular dynamics, estrogen production, ovulation and lutheinization of the corpus formation, simultaneously with other hormones, such as insulin-like growth factors (IGF) and pregnancy-associated plasma protein A (PAPP-A) which command the most important physical signs of heat and the events that will lead to ovulation. In this context, secretion of follicular prostaglandins appear and start the lyses on the follicle wall, which is associated with the rise of nitric oxide synthase (NOS) that increases the ovarian blood flow and consequently activates the vasoactive peptides angiotensin II (Ang II), endothelin-1 (ET-1) and atrial natriuretic peptide (ANP), representing a great part in the hormonal and methabolite integrated net involved in growth, development and follicle ovulation. This way, wider knowledge of the events that lead to the formation and the ovulation of the oocyte in the mare is necessary, so we may have an adequate female breeding management.


Assuntos
Feminino , Animais , Cavalos , Estro/fisiologia , Fator de Crescimento Insulin-Like I , Folículo Ovariano , Hormônio Liberador de Gonadotropina
19.
Vet. foco ; 6(1): 87-94, jul.-dez. 2008.
Artigo em Português | VETINDEX | ID: biblio-1502748

Resumo

Há mais de duas décadas os principais avanços têm sido realizados na identificação de peptídeos que atuam no hipotálamo, sendo produzidos local ou perifericamente, e que partici¬pem do processo homeostático da energia. Neste contexto, a grelina, peptídeo orexígeno de 28 aminoácidos que está primariamente envolvido no controle da ingestão de alimentos e na secre¬ção do hormônio do crescimento, propicia novos entendimentos quanto à existência de um eixo hipotalâmico-hipofisário-gástrico, que provê além do controle endócrino da homeostase por meio da secreção do hormônio do crescimento (GH) e da motilidade intestinal o controle do eixo reprodutivo. Este eixo é altamente dependente do estado nutricional. Onde a grelina atuando central e perifericamente, poderá ser descrita como um novo mediador de ligação entre o estado nutricional e o eixo hipotalâmico-hipofisário-gonadal. A ação reprodutiva da grelina não está, aparentemente, restrita à sua expressão e ação direta nas gônadas. Ações extragonadais dentro do eixo reprodutivo também têm sido documentadas, embora os dados sejam escassos. Assim, o isolamento e a caracterização da grelina têm possibilitado o entendimento da fisiologia do anabolismo, do comportamento ingestivo e da homeostase nutricional ligada à reprodução, por meio da secreção do GH e da motilidade gastrintestinal que interage com o cérebro


Since two decades, the main advances have been carried out on identification of peptides that are produced or localized in the hypothalamus and play a role in the energy homeostatic process. With regard to this, ghrelin, a 28-aminoacids orexigen peptide, is involved in the control of feed intake and in the growth hormone secretion, leading to new understanding about the existence of hypothalamic-pituitary-gastric axis that provide homeostasis endocrine control through the growth hormone (GH) secretion and intestinal motility. Reproductive axis is highly dependent of nutritional status, thus, ghrelin acting central and peripherically, may be one of the mediators of nutritional status to the hypothalamic-pituitary-gonadal axis. Ghrelin reproductive action is not, apparently, restrict to its expression and direct action on the gonads. Extra-gonadal actions within reproductive axis also have been reported, although data are rare. Thus, ghrelin isolation and characterization have made possible the understanding of anabolism and intake behavior physiology, and nutritional homeostasis linked to reproduction, through growth hormone (GH) secretion and gastrointestinal motility that interact with brain


Assuntos
Humanos , Animais , Grelina
20.
Vet. Foco ; 6(1): 87-94, jul.-dez. 2008.
Artigo em Português | VETINDEX | ID: vti-3338

Resumo

Há mais de duas décadas os principais avanços têm sido realizados na identificação de peptídeos que atuam no hipotálamo, sendo produzidos local ou perifericamente, e que partici¬pem do processo homeostático da energia. Neste contexto, a grelina, peptídeo orexígeno de 28 aminoácidos que está primariamente envolvido no controle da ingestão de alimentos e na secre¬ção do hormônio do crescimento, propicia novos entendimentos quanto à existência de um eixo hipotalâmico-hipofisário-gástrico, que provê além do controle endócrino da homeostase por meio da secreção do hormônio do crescimento (GH) e da motilidade intestinal o controle do eixo reprodutivo. Este eixo é altamente dependente do estado nutricional. Onde a grelina atuando central e perifericamente, poderá ser descrita como um novo mediador de ligação entre o estado nutricional e o eixo hipotalâmico-hipofisário-gonadal. A ação reprodutiva da grelina não está, aparentemente, restrita à sua expressão e ação direta nas gônadas. Ações extragonadais dentro do eixo reprodutivo também têm sido documentadas, embora os dados sejam escassos. Assim, o isolamento e a caracterização da grelina têm possibilitado o entendimento da fisiologia do anabolismo, do comportamento ingestivo e da homeostase nutricional ligada à reprodução, por meio da secreção do GH e da motilidade gastrintestinal que interage com o cérebro(AU)


Since two decades, the main advances have been carried out on identification of peptides that are produced or localized in the hypothalamus and play a role in the energy homeostatic process. With regard to this, ghrelin, a 28-aminoacids orexigen peptide, is involved in the control of feed intake and in the growth hormone secretion, leading to new understanding about the existence of hypothalamic-pituitary-gastric axis that provide homeostasis endocrine control through the growth hormone (GH) secretion and intestinal motility. Reproductive axis is highly dependent of nutritional status, thus, ghrelin acting central and peripherically, may be one of the mediators of nutritional status to the hypothalamic-pituitary-gonadal axis. Ghrelin reproductive action is not, apparently, restrict to its expression and direct action on the gonads. Extra-gonadal actions within reproductive axis also have been reported, although data are rare. Thus, ghrelin isolation and characterization have made possible the understanding of anabolism and intake behavior physiology, and nutritional homeostasis linked to reproduction, through growth hormone (GH) secretion and gastrointestinal motility that interact with brain(AU)


Assuntos
Humanos , Animais , Grelina
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